Vertical retracting thruster

Abstract

A vertical retracting thruster for providing thrust to a vessel is disclosed, suitable for mounting within a hull of the vessel. The vertical retracting thruster comprises a fixed base and a movable base. A vertical height adjusting assembly is configured to move the movable base relative to the fixed base in a vertical direction. A thrust motor is mounted to the movable base. The vertical retracting thruster has a retracted configuration, in which the propeller is retracted into the hull, and a deployed configuration, in which the propeller projects from the hull. The vertical retracting thruster is operable to move between the retracted configuration and the deployed configuration.

1 . A vertical retracting thruster for providing lateral thrust to a vessel, the vertical retracting thruster being suitable for mounting within a hull of the vessel,
 the vertical retracting thruster comprising:   a fixed base separating a thrust motor side and a propeller side of the vertical retracting thruster;   a movable base provided on the thrust motor side;   a vertical height adjusting assembly configured to move the movable base relative to the fixed base in a vertical direction;   a thrust motor mounted to the movable base;   a propeller with an outer diameter in the range from 100 mm to 150 mm, the propeller being provided on the propeller side;   a drive shaft linking the thrust motor to the propeller, the drive shaft extending in the vertical direction through the fixed base;   a drive shaft casing provided around the drive shaft; and   a seal disposed between an outer surface of the drive shaft casing and an internal surface of the fixed base, the seal providing water sealing between the thrust motor side and propeller side,   wherein the vertical retracting thruster has a retracted configuration, in which the propeller is retracted into the hull, and a deployed configuration, in which the propeller projects from the hull, the vertical retracting thruster being operable to move between the retracted configuration and the deployed configuration, and wherein, when in the retracted configuration, the distance in the vertical direction between the movable base and the fixed base is less than 200 mm, and   wherein the vertical height adjusting assembly comprises:   a height adjustment motor;   a gearbox with an output shaft, the output shaft being mechanically linked to the height adjustment motor;   a bearing plate attached to the gearbox such that the output shaft of the gearbox is rotatable in the bearing plate;   a height adjusting lead screw follower attached to the moveable base; and   a height adjusting lead screw connected to and rotatable with the output shaft of the gearbox, the height adjusting lead screw extending in the vertical direction from the gearbox to the height adjusting lead screw follower, the height adjusting lead screw coupling with the height adjusting lead screw follower such that the height adjusting lead screw follower and movable base move in the vertical direction when the height adjusting lead screw is rotated via the height adjustment motor and gearbox,   wherein the bearing plate and gearbox are attached to the fixed base with at least one fastener, said at least one fastener passing continuously through the bearing plate, the gearbox and the fixed base.   
     
     
         2 . A vertical retracting thruster according to  claim 1 , wherein the drive shaft has a fixed length in the vertical direction. 
     
     
         3 . A vertical retracting thruster according to any one of the preceding claims, wherein the total vertical height from the thruster motor to the propeller is less than 600 mm. 
     
     
         4 . A vertical retracting thruster according to any one of the preceding claims, wherein the thrust motor is an electric motor. 
     
     
         5 . A vertical retracting thruster for providing thrust to a vessel, the vertical retracting thruster being suitable for mounting within a hull of the vessel, the vertical retracting thruster comprising:
 a fixed base separating a thrust motor side and a propeller side of the vertical retracting thruster;   a movable base provided on the thrust motor side;   a vertical height adjusting assembly configured to move the movable base relative to the fixed base in a vertical direction;   a thrust motor mounted to the movable base;   a propeller with an outer diameter in the range from 100 mm to 150 mm, the propeller being provided on the propeller side;   a drive shaft linking the thrust motor to the propeller, the drive shaft extending in the vertical direction through the fixed base;   a drive shaft casing provided around the drive shaft;   a seal disposed between an outer surface of the drive shaft casing and an internal surface of the fixed base, the seal providing water sealing between the thrust motor side and propeller side,   wherein the vertical retracting thruster has a retracted configuration, in which the propeller is retracted into the hull, and a deployed configuration, in which the propeller projects from the hull, the vertical retracting thruster being operable to move between the retracted configuration and the deployed configuration, and wherein, when in the retracted configuration, the distance in the vertical direction between the movable base and the fixed base is less than 200 mm,   and wherein the vertical retracting thruster further comprises a steering arrangement for control of the direction of an axis of rotation of the propeller and thereby the direction of thrust at least when the vertical retracting thruster is in the deployed configuration, the steering arrangement being configured to rotate the thrust motor, the drive shaft casing and the propeller with respect to the movable base and with respect to the fixed base.   
     
     
         6 . A vertical retracting thruster according to  claim 5  wherein the vertical height adjusting assembly comprises:
 a height adjustment motor; 
 a gearbox with an output shaft, the output shaft being mechanically linked to the height adjustment motor; 
 a bearing plate attached to the gearbox such that the output shaft of the gearbox is rotatable in the bearing plate; 
 a height adjusting lead screw follower attached to the moveable base; and 
 a height adjusting lead screw connected to and rotatable with the output shaft of the gearbox, the height adjusting lead screw extending in the vertical direction from the gearbox to the height adjusting lead screw follower, the height adjusting lead screw coupling with the height adjusting lead screw follower such that the height adjusting lead screw follower and movable base move in the vertical direction when the height adjusting lead screw is rotated via the height adjustment motor and gearbox. 
 
     
     
         7 . A vertical retracting thruster according to  claim 6  wherein the bearing plate and gearbox are attached to the fixed base with at least one fastener, said at least one fastener passing continuously through the bearing plate, the gearbox and the fixed base. 
     
     
         8 . A vertical retracting thruster according to any one of  claims 5  to  7  wherein the steering arrangement comprises a steering motor fixed with respect to the movable base, the steering motor configured to rotate the thrust motor, the drive shaft casing and the propeller with respect to the movable base and with respect to the fixed base. 
     
     
         9 . A vertical retracting thruster according to any one of  claims 5  to  8  wherein the steering arrangement comprises a slew ring bearing arranged to allow rotation between the drive shaft casing and the movable base and to retain the drive shaft casing in a vertical direction with respect to the movable base. 
     
     
         10 . A vertical retracting thruster according to any one of  claims 5  to  9 , wherein the drive shaft has a fixed length in the vertical direction. 
     
     
         11 . A vertical retracting thruster according to any one of  claims 5  to  10 , wherein the total vertical height from the thruster motor to the propeller is less than 600 mm. 
     
     
         12 . A vertical retracting thruster according to any one of  claims 5  to  11 , wherein the thrust motor is an electric motor. 
     
     
         13 . A vertical retracting thruster for providing thrust to a vessel, the vertical retracting thruster being suitable for mounting within a hull of the vessel, the vertical retracting thruster comprising:
 a fixed base for mounting with respect to the hull;   a movable base;   a vertical height adjusting assembly;   a thrust motor;   a propeller with an outer diameter in the range from 100 mm to 250 mm;   wherein the vertical retracting thruster has a retracted configuration, in which the propeller is retracted into the hull, and a deployed configuration, in which the propeller projects from the hull, the vertical retracting thruster being operable to move between the retracted configuration and the deployed configuration,   the vertical retracting thruster further comprising:   a drive shaft linking the thrust motor to the propeller, the drive shaft extending in the vertical direction through the fixed base when the vertical retracting thruster is in the retracted configuration;   a drive shaft casing provided around at least part of the drive shaft and extending from the movable base and through the fixed base;   a seal disposed between an outer surface of the drive shaft casing and an internal surface of the fixed base,   wherein the thrust motor is contained, at least in part, within the drive shaft casing, the vertical height adjusting assembly being configured to move the movable base, the drive shaft casing, the thrust motor and the drive shaft relative to the fixed base in a vertical direction.   
     
     
         14 . A vertical retracting thruster according to  claim 13  wherein the thrust motor is contained, in its entirety, within the drive shaft casing. 
     
     
         15 . A vertical retracting thruster according to  claim 13  or  claim 14  further comprising a steering arrangement for control of the direction of an axis of rotation of the propeller and thereby the direction of thrust at least when the vertical retracting thruster is in the deployed configuration. 
     
     
         16 . A vertical retracting thruster according to  claim 15  wherein the steering arrangement is configured to rotate the thrust motor, the drive shaft casing and the propeller with respect to the movable base and with respect to the fixed base. 
     
     
         17 . A vertical retracting thruster according to  claim 15  or  claim 16  wherein the steering arrangement comprises a steering motor fixed with respect to the movable base. 
     
     
         18 . A vertical retracting thruster according to any one of  claims 13  to  17  further comprising:
 a height adjustment motor; 
 a gearbox with an output shaft, the output shaft being mechanically linked to the height adjustment motor; 
 a bearing plate attached to the gearbox such that the output shaft of the gearbox is rotatable in the bearing plate; 
 a height adjusting lead screw follower attached to the moveable base; and 
 a height adjusting lead screw connected to and rotatable with the output shaft of the gearbox. 
 
     
     
         19 . A vessel with a vertical retracting thruster according to any one of  claims 1  to  18  installed inside a hull of the vessel. 
     
     
         20 . A vessel according to  claim 19 , wherein the vessel is a pontoon style vessel. 
     
     
         21 . A vessel according to  claim 20 , wherein the pontoon style vessel comprises three hulls. 
     
     
         22 . A vessel according to  claim 21 , wherein the vertical retracting thruster is installed inside the central hull. 
     
     
         23 . A vessel according to the any one of  claims 19  to  22 , wherein a vertical retracting thruster according to any one of  claims 1  to  18  is installed inside a bow region of the hull and another vertical retracting thruster, of a same or different type, according to any one of  claims 1  to  18  is installed inside a stern region of the hull.